On demand positioning reference signals and per band deployment aspects

ABSTRACT

Disclosed are techniques for wireless communication. In an aspect, a user equipment (UE) transmits a request for a first set of base stations to transmit on demand positioning reference signals (PRS) in a first band, measures the on demand PRS from the first set of base stations in the first band, measures periodic PRS from a second set of base stations operating in a second band, and sends, to a positioning entity, positioning measurements of at least the on demand PRS and the periodic PRS.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application for Patent is a continuation of U.S. applicationSer. No. 17/218,669, entitled “ON DEMAND POSITIONING REFERENCE SIGNALSAND PER BAND DEPLOYMENT ASPECTS,” filed Mar. 31, 2021, which claims thebenefit of U.S. Provisional Application No. 63/005,082, entitled “ONDEMAND POSITIONING REFERENCE SIGNALS AND PER BAND DEPLOYMENT ASPECTS,”filed Apr. 3, 2020, each of which is assigned to the assignee hereof,and expressly incorporated herein by reference in its entirety.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

Aspects of the disclosure relate generally to wireless communications.

2. Description of the Related Art

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingcellular and personal communications service (PCS) systems. Examples ofknown cellular systems include the cellular analog advanced mobile phonesystem (AMPS), and digital cellular systems based on code divisionmultiple access (CDMA), frequency division multiple access (FDMA), timedivision multiple access (TDMA), the Global System for Mobilecommunications (GSM), etc.

A fifth generation (5G) wireless standard, referred to as New Radio(NR), calls for higher data transfer speeds, greater numbers ofconnections, and better coverage, among other improvements. The 5Gstandard, according to the Next Generation Mobile Networks Alliance, isdesigned to provide data rates of several tens of megabits per second toeach of tens of thousands of users, with 1 gigabit per second to tens ofworkers on an office floor. Several hundreds of thousands ofsimultaneous connections should be supported in order to support largesensor deployments. Consequently, the spectral efficiency of 5G mobilecommunications should be significantly enhanced compared to the current4G standard. Furthermore, signaling efficiencies should be enhanced andlatency should be substantially reduced compared to current standards.

SUMMARY

The following presents a simplified summary relating to one or moreaspects disclosed herein. Thus, the following summary should not beconsidered an extensive overview relating to all contemplated aspects,nor should the following summary be considered to identify key orcritical elements relating to all contemplated aspects or to delineatethe scope associated with any particular aspect. Accordingly, thefollowing summary has the sole purpose to present certain conceptsrelating to one or more aspects relating to the mechanisms disclosedherein in a simplified form to precede the detailed descriptionpresented below.

In an aspect, a method of wireless communication performed by a userequipment (UE), includes transmitting a first request for a first set ofbase stations to transmit first on demand positioning reference signals(PRS) in a first band, measuring the first on demand PRS from the firstset of base stations in the first band, measuring periodic PRS from asecond set of base stations operating in a second band, and sending, toa positioning entity, positioning measurements of at least the first ondemand PRS and the periodic PRS.

In an aspect, a UE includes a memory, at least one transceiver, and atleast one processor communicatively coupled to the memory and the atleast one transceiver, the at least one processor configured to causethe at least one transceiver to transmit a first request for a first setof base stations to transmit first on demand PRS in a first band,measure the first on demand PRS from the first set of base stations inthe first band, measure periodic PRS from a second set of base stationsoperating in a second band, and send, to a positioning entity,positioning measurements of at least the first on demand PRS and theperiodic PRS.

In an aspect, a UE includes means for transmitting a first request for afirst set of base stations to transmit first on demand PRS in a firstband, means for measuring the first on demand PRS from the first set ofbase stations in the first band, means for measuring periodic PRS from asecond set of base stations operating in a second band, and means forsending, to a positioning entity, positioning measurements of at leastthe first on demand PRS and the periodic PRS.

In an aspect, a non-transitory computer-readable medium storingcomputer-executable instructions includes computer-executableinstructions comprising at least one instruction instructing a UE totransmit a first request for a first set of base stations to transmitfirst on demand PRS in a first band, at least one instructioninstructing the UE to measure the first on demand PRS from the first setof base stations in the first band, at least one instruction instructingthe UE to measure periodic PRS from a second set of base stationsoperating in a second band, and at least one instruction instructing theUE to send, to a positioning entity, positioning measurements of atleast the first on demand PRS and the periodic PRS.

Other objects and advantages associated with the aspects disclosedherein will be apparent to those skilled in the art based on theaccompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are presented to aid in the description ofvarious aspects of the disclosure and are provided solely forillustration of the aspects and not limitation thereof.

FIG. 1 illustrates an example wireless communications system, accordingto aspects of the disclosure.

FIGS. 2A and 2B illustrate example wireless network structures,according to aspects of the disclosure.

FIGS. 3A to 3C are simplified block diagrams of several sample aspectsof components that may be employed in a user equipment (UE), a basestation, and a network entity, respectively, and configured to supportcommunications as taught herein.

FIGS. 4A and 4B are diagrams illustrating example frame structures andchannels within the frame structures, according to aspects of thedisclosure.

FIG. 5 is an example call flow between a UE, a serving base station, anda location server, according to aspects of the disclosure.

FIG. 6 illustrates an example method of wireless communication,according to aspects of the disclosure.

DETAILED DESCRIPTION

Aspects of the disclosure are provided in the following description andrelated drawings directed to various examples provided for illustrationpurposes. Alternate aspects may be devised without departing from thescope of the disclosure. Additionally, well-known elements of thedisclosure will not be described in detail or will be omitted so as notto obscure the relevant details of the disclosure.

The words “exemplary” and/or “example” are used herein to mean “servingas an example, instance, or illustration.” Any aspect described hereinas “exemplary” and/or “example” is not necessarily to be construed aspreferred or advantageous over other aspects. Likewise, the term“aspects of the disclosure” does not require that all aspects of thedisclosure include the discussed feature, advantage or mode ofoperation.

Those of skill in the art will appreciate that the information andsignals described below may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the description below may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof, depending inpart on the particular application, in part on the desired design, inpart on the corresponding technology, etc.

Further, many aspects are described in terms of sequences of actions tobe performed by, for example, elements of a computing device. It will berecognized that various actions described herein can be performed byspecific circuits (e.g., application specific integrated circuits(ASICs)), by program instructions being executed by one or moreprocessors, or by a combination of both. Additionally, the sequence(s)of actions described herein can be considered to be embodied entirelywithin any form of non-transitory computer-readable storage mediumhaving stored therein a corresponding set of computer instructions that,upon execution, would cause or instruct an associated processor of adevice to perform the functionality described herein. Thus, the variousaspects of the disclosure may be embodied in a number of differentforms, all of which have been contemplated to be within the scope of theclaimed subject matter. In addition, for each of the aspects describedherein, the corresponding form of any such aspects may be describedherein as, for example, “logic configured to” perform the describedaction.

As used herein, the terms “user equipment” (UE) and “base station” arenot intended to be specific or otherwise limited to any particular radioaccess technology (RAT), unless otherwise noted. In general, a UE may beany wireless communication device (e.g., a mobile phone, router, tabletcomputer, laptop computer, consumer asset locating device, wearable(e.g., smartwatch, glasses, augmented reality (AR)/virtual reality (VR)headset, etc.), vehicle (e.g., automobile, motorcycle, bicycle, etc.),Internet of Things (IoT) device, etc.) used by a user to communicateover a wireless communications network. A UE may be mobile or may (e.g.,at certain times) be stationary, and may communicate with a radio accessnetwork (RAN). As used herein, the term “UE” may be referred tointerchangeably as an “access terminal” or “AT,” a “client device,” a“wireless device,” a “subscriber device,” a “subscriber terminal,” a“subscriber station,” a “user terminal” or “UT,” a “mobile device,” a“mobile terminal,” a “mobile station,” or variations thereof. Generally,UEs can communicate with a core network via a RAN, and through the corenetwork the UEs can be connected with external networks such as theInternet and with other UEs. Of course, other mechanisms of connectingto the core network and/or the Internet are also possible for the UEs,such as over wired access networks, wireless local area network (WLAN)networks (e.g., based on the Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 specification, etc.) and so on.

A base station may operate according to one of several RATs incommunication with UEs depending on the network in which it is deployed,and may be alternatively referred to as an access point (AP), a networknode, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), aNew Radio (NR) Node B (also referred to as a gNB or gNodeB), etc. A basestation may be used primarily to support wireless access by UEs,including supporting data, voice, and/or signaling connections for thesupported UEs. In some systems a base station may provide purely edgenode signaling functions while in other systems it may provideadditional control and/or network management functions. A communicationlink through which UEs can send signals to a base station is called anuplink (UL) channel (e.g., a reverse traffic channel, a reverse controlchannel, an access channel, etc.). A communication link through whichthe base station can send signals to UEs is called a downlink (DL) orforward link channel (e.g., a paging channel, a control channel, abroadcast channel, a forward traffic channel, etc.). As used herein theterm traffic channel (TCH) can refer to either an uplink/reverse ordownlink/forward traffic channel.

The term “base station” may refer to a single physicaltransmission-reception point (TRP) or to multiple physical TRPs that mayor may not be co-located. For example, where the term “base station”refers to a single physical TRP, the physical TRP may be an antenna ofthe base station corresponding to a cell (or several cell sectors) ofthe base station. Where the term “base station” refers to multipleco-located physical TRPs, the physical TRPs may be an array of antennas(e.g., as in a multiple-input multiple-output (MIMO) system or where thebase station employs beamforming) of the base station. Where the term“base station” refers to multiple non-co-located physical TRPs, thephysical TRPs may be a distributed antenna system (DAS) (a network ofspatially separated antennas connected to a common source via atransport medium) or a remote radio head (RRH) (a remote base stationconnected to a serving base station). Alternatively, the non-co-locatedphysical TRPs may be the serving base station receiving the measurementreport from the UE and a neighbor base station whose reference radiofrequency (RF) signals the UE is measuring. Because a TRP is the pointfrom which a base station transmits and receives wireless signals, asused herein, references to transmission from or reception at a basestation are to be understood as referring to a particular TRP of thebase station.

In some implementations that support positioning of UEs, a base stationmay not support wireless access by UEs (e.g., may not support data,voice, and/or signaling connections for UEs), but may instead transmitreference signals to UEs to be measured by the UEs, and/or may receiveand measure signals transmitted by the UEs. Such a base station may bereferred to as a positioning beacon (e.g., when transmitting signals toUEs) and/or as a location measurement unit (e.g., when receiving andmeasuring signals from UEs).

An “RF signal” comprises an electromagnetic wave of a given frequencythat transports information through the space between a transmitter anda receiver. As used herein, a transmitter may transmit a single “RFsignal” or multiple “RF signals” to a receiver. However, the receivermay receive multiple “RF signals” corresponding to each transmitted RFsignal due to the propagation characteristics of RF signals throughmultipath channels. The same transmitted RF signal on different pathsbetween the transmitter and receiver may be referred to as a “multipath”RF signal.

FIG. 1 illustrates an example wireless communications system 100,according to aspects of the disclosure. The wireless communicationssystem 100 (which may also be referred to as a wireless wide areanetwork (WWAN)) may include various base stations 102 (labeled “BS”) andvarious UEs 104. The base stations 102 may include macro cell basestations (high power cellular base stations) and/or small cell basestations (low power cellular base stations). In an aspect, the macrocell base station may include eNBs and/or ng-eNBs where the wirelesscommunications system 100 corresponds to an LTE network, or gNBs wherethe wireless communications system 100 corresponds to a NR network, or acombination of both, and the small cell base stations may includefemtocells, picocells, microcells, etc.

The base stations 102 may collectively form a RAN and interface with acore network 170 (e.g., an evolved packet core (EPC) or a 5G core (5GC))through backhaul links 122, and through the core network 170 to one ormore location servers 172 (e.g., a location management function (LMF) ora secure user plane location (SUPL) location platform (SLP)). Thelocation server(s) 172 may be part of core network 170 or may beexternal to core network 170. In addition to other functions, the basestations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/5GC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, one or more cellsmay be supported by a base station 102 in each geographic coverage area110. A “cell” is a logical communication entity used for communicationwith a base station (e.g., over some frequency resource, referred to asa carrier frequency, component carrier, carrier, band, or the like), andmay be associated with an identifier (e.g., a physical cell identifier(PCI), a virtual cell identifier (VCI), a cell global identifier (CGI))for distinguishing cells operating via the same or a different carrierfrequency. In some cases, different cells may be configured according todifferent protocol types (e.g., machine-type communication (MTC),narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others)that may provide access for different types of UEs. Because a cell issupported by a specific base station, the term “cell” may refer toeither or both of the logical communication entity and the base stationthat supports it, depending on the context. In some cases, the term“cell” may also refer to a geographic coverage area of a base station(e.g., a sector), insofar as a carrier frequency can be detected andused for communication within some portion of geographic coverage areas110.

While neighboring macro cell base station 102 geographic coverage areas110 may partially overlap (e.g., in a handover region), some of thegeographic coverage areas 110 may be substantially overlapped by alarger geographic coverage area 110. For example, a small cell (SC) basestation 102′ may have a geographic coverage area 110′ that substantiallyoverlaps with the geographic coverage area 110 of one or more macro cellbase stations 102. A network that includes both small cell and macrocell base stations may be known as a heterogeneous network. Aheterogeneous network may also include home eNBs (HeNBs), which mayprovide service to a restricted group known as a closed subscriber group(CSG).

The communication links 120 between the base stations 102 and the UEs104 may include uplink (also referred to as reverse link) transmissionsfrom a UE 104 to a base station 102 and/or downlink (also referred to asforward link) transmissions from a base station 102 to a UE 104. Thecommunication links 120 may use MIMO antenna technology, includingspatial multiplexing, beamforming, and/or transmit diversity. Thecommunication links 120 may be through one or more carrier frequencies.Allocation of carriers may be asymmetric with respect to downlink anduplink (e.g., more or less carriers may be allocated for downlink thanfor uplink).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) or listen before talk (LBT) procedureprior to communicating in order to determine whether the channel isavailable.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or NRtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. NR in unlicensed spectrum maybe referred to as NR-U. LTE in an unlicensed spectrum may be referred toas LTE-U, licensed assisted access (LAA), or MulteFire.

The wireless communications system 100 may further include a millimeterwave (mmW) base station 180 that may operate in mmW frequencies and/ornear mmW frequencies in communication with a UE 182. Extremely highfrequency (EHF) is part of the RF in the electromagnetic spectrum. EHFhas a range of 30 GHz to 300 GHz and a wavelength between 1 millimeterand 10 millimeters. Radio waves in this band may be referred to as amillimeter wave. Near mmW may extend down to a frequency of 3 GHz with awavelength of 100 millimeters. The super high frequency (SHF) bandextends between 3 GHz and 30 GHz, also referred to as centimeter wave.Communications using the mmW/near mmW radio frequency band have highpath loss and a relatively short range. The mmW base station 180 and theUE 182 may utilize beamforming (transmit and/or receive) over a mmWcommunication link 184 to compensate for the extremely high path lossand short range. Further, it will be appreciated that in alternativeconfigurations, one or more base stations 102 may also transmit usingmmW or near mmW and beamforming. Accordingly, it will be appreciatedthat the foregoing illustrations are merely examples and should not beconstrued to limit the various aspects disclosed herein.

Transmit beamforming is a technique for focusing an RF signal in aspecific direction. Traditionally, when a network node (e.g., a basestation) broadcasts an RF signal, it broadcasts the signal in alldirections (omni-directionally). With transmit beamforming, the networknode determines where a given target device (e.g., a UE) is located(relative to the transmitting network node) and projects a strongerdownlink RF signal in that specific direction, thereby providing afaster (in terms of data rate) and stronger RF signal for the receivingdevice(s). To change the directionality of the RF signal whentransmitting, a network node can control the phase and relativeamplitude of the RF signal at each of the one or more transmitters thatare broadcasting the RF signal. For example, a network node may use anarray of antennas (referred to as a “phased array” or an “antennaarray”) that creates a beam of RF waves that can be “steered” to pointin different directions, without actually moving the antennas.Specifically, the RF current from the transmitter is fed to theindividual antennas with the correct phase relationship so that theradio waves from the separate antennas add together to increase theradiation in a desired direction, while cancelling to suppress radiationin undesired directions.

Transmit beams may be quasi-co-located, meaning that they appear to thereceiver (e.g., a UE) as having the same parameters, regardless ofwhether or not the transmitting antennas of the network node themselvesare physically co-located. In NR, there are four types ofquasi-co-location (QCL) relations. Specifically, a QCL relation of agiven type means that certain parameters about a target reference RFsignal on a target beam can be derived from information about a sourcereference RF signal on a source beam. If the source reference RF signalis QCL Type A, the receiver can use the source reference RF signal toestimate the Doppler shift, Doppler spread, average delay, and delayspread of a target reference RF signal transmitted on the same channel.If the source reference RF signal is QCL Type B, the receiver can usethe source reference RF signal to estimate the Doppler shift and Dopplerspread of a target reference RF signal transmitted on the same channel.If the source reference RF signal is QCL Type C, the receiver can usethe source reference RF signal to estimate the Doppler shift and averagedelay of a target reference RF signal transmitted on the same channel.If the source reference RF signal is QCL Type D, the receiver can usethe source reference RF signal to estimate the spatial receive parameterof a target reference RF signal transmitted on the same channel.

In receive beamforming, the receiver uses a receive beam to amplify RFsignals detected on a given channel. For example, the receiver canincrease the gain setting and/or adjust the phase setting of an array ofantennas in a particular direction to amplify (e.g., to increase thegain level of) the RF signals received from that direction. Thus, when areceiver is said to beamform in a certain direction, it means the beamgain in that direction is high relative to the beam gain along otherdirections, or the beam gain in that direction is the highest comparedto the beam gain in that direction of all other receive beams availableto the receiver. This results in a stronger received signal strength(e.g., reference signal received power (RSRP), reference signal receivedquality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) ofthe RF signals received from that direction.

Receive beams may be spatially related. A spatial relation means thatparameters for a transmit beam for a second reference signal can bederived from information about a receive beam for a first referencesignal. For example, a UE may use a particular receive beam to receiveone or more reference downlink reference signals (e.g., positioningreference signals (PRS), tracking reference signals (TRS), phasetracking reference signal (PTRS), cell-specific reference signals (CRS),channel state information reference signals (CSI-RS), primarysynchronization signals (PSS), secondary synchronization signals (SSS),synchronization signal blocks (SSBs), etc.) from a base station. The UEcan then form a transmit beam for sending one or more uplink referencesignals (e.g., uplink positioning reference signals (UL-PRS), soundingreference signal (SRS), demodulation reference signals (DMRS), PTRS,etc.) to that base station based on the parameters of the receive beam.

Note that a “downlink” beam may be either a transmit beam or a receivebeam, depending on the entity forming it. For example, if a base stationis forming the downlink beam to transmit a reference signal to a UE, thedownlink beam is a transmit beam. If the UE is forming the downlinkbeam, however, it is a receive beam to receive the downlink referencesignal. Similarly, an “uplink” beam may be either a transmit beam or areceive beam, depending on the entity forming it. For example, if a basestation is forming the uplink beam, it is an uplink receive beam, and ifa UE is forming the uplink beam, it is an uplink transmit beam.

In 5G, the frequency spectrum in which wireless nodes (e.g., basestations 102/180, UEs 104/182) operate is divided into multiplefrequency ranges, FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In amulti-carrier system, such as 5G, one of the carrier frequencies isreferred to as the “primary carrier” or “anchor carrier” or “primaryserving cell” or “PCell,” and the remaining carrier frequencies arereferred to as “secondary carriers” or “secondary serving cells” or“SCells.” In carrier aggregation, the anchor carrier is the carrieroperating on the primary frequency (e.g., FR1) utilized by a UE 104/182and the cell in which the UE 104/182 either performs the initial radioresource control (RRC) connection establishment procedure or initiatesthe RRC connection re-establishment procedure. The primary carriercarries all common and UE-specific control channels, and may be acarrier in a licensed frequency (however, this is not always the case).A secondary carrier is a carrier operating on a second frequency (e.g.,FR2) that may be configured once the RRC connection is establishedbetween the UE 104 and the anchor carrier and that may be used toprovide additional radio resources. In some cases, the secondary carriermay be a carrier in an unlicensed frequency. The secondary carrier maycontain only necessary signaling information and signals, for example,those that are UE-specific may not be present in the secondary carrier,since both primary uplink and downlink carriers are typicallyUE-specific. This means that different UEs 104/182 in a cell may havedifferent downlink primary carriers. The same is true for the uplinkprimary carriers. The network is able to change the primary carrier ofany UE 104/182 at any time. This is done, for example, to balance theload on different carriers. Because a “serving cell” (whether a PCell oran SCell) corresponds to a carrier frequency/component carrier overwhich some base station is communicating, the term “cell,” “servingcell,” “component carrier,” “carrier frequency,” and the like can beused interchangeably.

For example, still referring to FIG. 1 , one of the frequencies utilizedby the macro cell base stations 102 may be an anchor carrier (or“PCell”) and other frequencies utilized by the macro cell base stations102 and/or the mmW base station 180 may be secondary carriers(“SCells”). The simultaneous transmission and/or reception of multiplecarriers enables the UE 104/182 to significantly increase its datatransmission and/or reception rates. For example, two 20 MHz aggregatedcarriers in a multi-carrier system would theoretically lead to atwo-fold increase in data rate (i.e., 40 MHz), compared to that attainedby a single 20 MHz carrier.

The wireless communications system 100 may further include a UE 164 thatmay communicate with a macro cell base station 102 over a communicationlink 120 and/or the mmW base station 180 over a mmW communication link184. For example, the macro cell base station 102 may support a PCelland one or more SCells for the UE 164 and the mmW base station 180 maysupport one or more SCells for the UE 164.

In the example of FIG. 1 , one or more Earth orbiting satellitepositioning system (SPS) space vehicles (SVs) 112 (e.g., satellites) maybe used as an independent source of location information for any of theillustrated UEs (shown in FIG. 1 as a single UE 104 for simplicity). AUE 104 may include one or more dedicated SPS receivers specificallydesigned to receive SPS signals 124 for deriving geo locationinformation from the SVs 112. An SPS typically includes a system oftransmitters (e.g., SVs 112) positioned to enable receivers (e.g., UEs104) to determine their location on or above the Earth based, at leastin part, on signals (e.g., SPS signals 124) received from thetransmitters. Such a transmitter typically transmits a signal markedwith a repeating pseudo-random noise (PN) code of a set number of chips.While typically located in SVs 112, transmitters may sometimes belocated on ground-based control stations, base stations 102, and/orother UEs 104.

The use of SPS signals 124 can be augmented by various satellite-basedaugmentation systems (SBAS) that may be associated with or otherwiseenabled for use with one or more global and/or regional navigationsatellite systems. For example an SBAS may include an augmentationsystem(s) that provides integrity information, differential corrections,etc., such as the Wide Area Augmentation System (WAAS), the EuropeanGeostationary Navigation Overlay Service (EGNOS), the Multi-functionalSatellite Augmentation System (MSAS), the Global Positioning System(GPS) Aided Geo Augmented Navigation or GPS and Geo Augmented Navigationsystem (GAGAN), and/or the like. Thus, as used herein, an SPS mayinclude any combination of one or more global and/or regional navigationsatellite systems and/or augmentation systems, and SPS signals 124 mayinclude SPS, SPS-like, and/or other signals associated with such one ormore SPS.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links (referred to as “sidelinks”). In the example ofFIG. 1 , UE 190 has a D2D P2P link 192 with one of the UEs 104 connectedto one of the base stations 102 (e.g., through which UE 190 mayindirectly obtain cellular connectivity) and a D2D P2P link 194 withWLAN STA 152 connected to the WLAN AP 150 (through which UE 190 mayindirectly obtain WLAN-based Internet connectivity). In an example, theD2D P2P links 192 and 194 may be supported with any well-known D2D RAT,such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, and so on.

FIG. 2A illustrates an example wireless network structure 200. Forexample, a 5GC 210 (also referred to as a Next Generation Core (NGC))can be viewed functionally as control plane functions 214 (e.g., UEregistration, authentication, network access, gateway selection, etc.)and user plane functions 212, (e.g., UE gateway function, access to datanetworks, IP routing, etc.) which operate cooperatively to form the corenetwork. User plane interface (NG-U) 213 and control plane interface(NG-C) 215 connect the gNB 222 to the 5GC 210 and specifically to thecontrol plane functions 214 and user plane functions 212. In anadditional configuration, an ng-eNB 224 may also be connected to the 5GC210 via NG-C 215 to the control plane functions 214 and NG-U 213 to userplane functions 212. Further, ng-eNB 224 may directly communicate withgNB 222 via a backhaul connection 223. In some configurations, a NextGeneration RAN (NG-RAN) 220 may only have one or more gNBs 222, whileother configurations include one or more of both ng-eNBs 224 and gNBs222. Either gNB 222 or ng-eNB 224 may communicate with UEs 204 (e.g.,any of the UEs depicted in FIG. 1 ). Another optional aspect may includelocation server 230, which may be in communication with the 5GC 210 toprovide location assistance for UEs 204. The location server 230 can beimplemented as a plurality of separate servers (e.g., physicallyseparate servers, different software modules on a single server,different software modules spread across multiple physical servers,etc.), or alternately may each correspond to a single server. Thelocation server 230 can be configured to support one or more locationservices for UEs 204 that can connect to the location server 230 via thecore network, 5GC 210, and/or via the Internet (not illustrated).Further, the location server 230 may be integrated into a component ofthe core network, or alternatively may be external to the core network.

FIG. 2B illustrates another example wireless network structure 250. A5GC 260 (which may correspond to 5GC 210 in FIG. 2A) can be viewedfunctionally as control plane functions, provided by an access andmobility management function (AMF) 264, and user plane functions,provided by a user plane function (UPF) 262, which operate cooperativelyto form the core network (i.e., 5GC 260). User plane interface 263 andcontrol plane interface 265 connect the ng-eNB 224 to the 5GC 260 andspecifically to UPF 262 and AMF 264, respectively. In an additionalconfiguration, a gNB 222 may also be connected to the 5GC 260 viacontrol plane interface 265 to AMF 264 and user plane interface 263 toUPF 262. Further, ng-eNB 224 may directly communicate with gNB 222 viathe backhaul connection 223, with or without gNB direct connectivity tothe 5GC 260. In some configurations, the NG-RAN 220 may only have one ormore gNBs 222, while other configurations include one or more of bothng-eNBs 224 and gNBs 222. Either gNB 222 or ng-eNB 224 may communicatewith UEs 204 (e.g., any of the UEs depicted in FIG. 1 ). The basestations of the NG-RAN 220 communicate with the AMF 264 over the N2interface and with the UPF 262 over the N3 interface.

The functions of the AMF 264 include registration management, connectionmanagement, reachability management, mobility management, lawfulinterception, transport for session management (SM) messages between theUE 204 and a session management function (SMF) 266, transparent proxyservices for routing SM messages, access authentication and accessauthorization, transport for short message service (SMS) messagesbetween the UE 204 and the short message service function (SMSF) (notshown), and security anchor functionality (SEAF). The AMF 264 alsointeracts with an authentication server function (AUSF) (not shown) andthe UE 204, and receives the intermediate key that was established as aresult of the UE 204 authentication process. In the case ofauthentication based on a UMTS (universal mobile telecommunicationssystem) subscriber identity module (USIM), the AMF 264 retrieves thesecurity material from the AUSF. The functions of the AMF 264 alsoinclude security context management (SCM). The SCM receives a key fromthe SEAF that it uses to derive access-network specific keys. Thefunctionality of the AMF 264 also includes location services managementfor regulatory services, transport for location services messagesbetween the UE 204 and an LMF 270 (which acts as a location server 230),transport for location services messages between the NG-RAN 220 and theLMF 270, evolved packet system (EPS) bearer identifier allocation forinterworking with the EPS, and UE 204 mobility event notification. Inaddition, the AMF 264 also supports functionalities for non-3GPP (ThirdGeneration Partnership Project) access networks.

Functions of the UPF 262 include acting as an anchor point forintra-/inter-RAT mobility (when applicable), acting as an externalprotocol data unit (PDU) session point of interconnect to a data network(not shown), providing packet routing and forwarding, packet inspection,user plane policy rule enforcement (e.g., gating, redirection, trafficsteering), lawful interception (user plane collection), traffic usagereporting, quality of service (QoS) handling for the user plane (e.g.,uplink/downlink rate enforcement, reflective QoS marking in thedownlink), uplink traffic verification (service data flow (SDF) to QoSflow mapping), transport level packet marking in the uplink anddownlink, downlink packet buffering and downlink data notificationtriggering, and sending and forwarding of one or more “end markers” tothe source RAN node. The UPF 262 may also support transfer of locationservices messages over a user plane between the UE 204 and a locationserver, such as an SLP 272.

The functions of the SMF 266 include session management, UE Internetprotocol (IP) address allocation and management, selection and controlof user plane functions, configuration of traffic steering at the UPF262 to route traffic to the proper destination, control of part ofpolicy enforcement and QoS, and downlink data notification. Theinterface over which the SMF 266 communicates with the AMF 264 isreferred to as the N11 interface.

Another optional aspect may include an LMF 270, which may be incommunication with the 5GC 260 to provide location assistance for UEs204. The LMF 270 can be implemented as a plurality of separate servers(e.g., physically separate servers, different software modules on asingle server, different software modules spread across multiplephysical servers, etc.), or alternately may each correspond to a singleserver. The LMF 270 can be configured to support one or more locationservices for UEs 204 that can connect to the LMF 270 via the corenetwork, 5GC 260, and/or via the Internet (not illustrated). The SLP 272may support similar functions to the LMF 270, but whereas the LMF 270may communicate with the AMF 264, NG-RAN 220, and UEs 204 over a controlplane (e.g., using interfaces and protocols intended to convey signalingmessages and not voice or data), the SLP 272 may communicate with UEs204 and external clients (not shown in FIG. 2B) over a user plane (e.g.,using protocols intended to carry voice and/or data like thetransmission control protocol (TCP) and/or IP).

FIGS. 3A, 3B, and 3C illustrate several example components (representedby corresponding blocks) that may be incorporated into a UE 302 (whichmay correspond to any of the UEs described herein), a base station 304(which may correspond to any of the base stations described herein), anda network entity 306 (which may correspond to or embody any of thenetwork functions described herein, including the location server 230and the LMF 270) to support the file transmission operations as taughtherein. It will be appreciated that these components may be implementedin different types of apparatuses in different implementations (e.g., inan ASIC, in a system-on-chip (SoC), etc.). The illustrated componentsmay also be incorporated into other apparatuses in a communicationsystem. For example, other apparatuses in a system may includecomponents similar to those described to provide similar functionality.Also, a given apparatus may contain one or more of the components. Forexample, an apparatus may include multiple transceiver components thatenable the apparatus to operate on multiple carriers and/or communicatevia different technologies.

The UE 302 and the base station 304 each include at least one wirelesswide area network (WWAN) transceiver 310 and 350, respectively,providing means for communicating (e.g., means for transmitting, meansfor receiving, means for measuring, means for tuning, means forrefraining from transmitting, etc.) via one or more wirelesscommunication networks (not shown), such as an NR network, an LTEnetwork, a GSM network, and/or the like. The WWAN transceivers 310 and350 may be connected to one or more antennas 316 and 356, respectively,for communicating with other network nodes, such as other UEs, accesspoints, base stations (e.g., eNBs, gNBs), etc., via at least onedesignated RAT (e.g., NR, LTE, GSM, etc.) over a wireless communicationmedium of interest (e.g., some set of time/frequency resources in aparticular frequency spectrum). The WWAN transceivers 310 and 350 may bevariously configured for transmitting and encoding signals 318 and 358(e.g., messages, indications, information, and so on), respectively,and, conversely, for receiving and decoding signals 318 and 358 (e.g.,messages, indications, information, pilots, and so on), respectively, inaccordance with the designated RAT. Specifically, the WWAN transceivers310 and 350 include one or more transmitters 314 and 354, respectively,for transmitting and encoding signals 318 and 358, respectively, and oneor more receivers 312 and 352, respectively, for receiving and decodingsignals 318 and 358, respectively.

The UE 302 and the base station 304 also include, at least in somecases, at least one short-range wireless transceiver 320 and 360,respectively. The short-range wireless transceivers 320 and 360 may beconnected to one or more antennas 326 and 366, respectively, and providemeans for communicating (e.g., means for transmitting, means forreceiving, means for measuring, means for tuning, means for refrainingfrom transmitting, etc.) with other network nodes, such as other UEs,access points, base stations, etc., via at least one designated RAT(e.g., WiFi, LTE-D, Bluetooth®, Zigbee®, Z-Wave®, PCS, dedicatedshort-range communications (DSRC), wireless access for vehicularenvironments (WAVE), near-field communication (NFC), etc.) over awireless communication medium of interest. The short-range wirelesstransceivers 320 and 360 may be variously configured for transmittingand encoding signals 328 and 368 (e.g., messages, indications,information, and so on), respectively, and, conversely, for receivingand decoding signals 328 and 368 (e.g., messages, indications,information, pilots, and so on), respectively, in accordance with thedesignated RAT. Specifically, the short-range wireless transceivers 320and 360 include one or more transmitters 324 and 364, respectively, fortransmitting and encoding signals 328 and 368, respectively, and one ormore receivers 322 and 362, respectively, for receiving and decodingsignals 328 and 368, respectively. As specific examples, the short-rangewireless transceivers 320 and 360 may be WiFi transceivers, Bluetooth®transceivers, Zigbee® and/or Z-Wave® transceivers, NFC transceivers, orvehicle-to-vehicle (V2V) and/or vehicle-to-everything (V2X)transceivers.

Transceiver circuitry including at least one transmitter and at leastone receiver may comprise an integrated device (e.g., embodied as atransmitter circuit and a receiver circuit of a single communicationdevice) in some implementations, may comprise a separate transmitterdevice and a separate receiver device in some implementations, or may beembodied in other ways in other implementations. In an aspect, atransmitter may include or be coupled to a plurality of antennas (e.g.,antennas 316, 326, 356, 366), such as an antenna array, that permits therespective apparatus to perform transmit “beamforming,” as describedherein. Similarly, a receiver may include or be coupled to a pluralityof antennas (e.g., antennas 316, 326, 356, 366), such as an antennaarray, that permits the respective apparatus to perform receivebeamforming, as described herein. In an aspect, the transmitter andreceiver may share the same plurality of antennas (e.g., antennas 316,326, 356, 366), such that the respective apparatus can only receive ortransmit at a given time, not both at the same time. A wirelesscommunication device (e.g., one or both of the transceivers 310 and 320and/or 350 and 360) of the UE 302 and/or the base station 304 may alsocomprise a network listen module (NLM) or the like for performingvarious measurements.

The UE 302 and the base station 304 also include, at least in somecases, satellite positioning systems (SPS) receivers 330 and 370. TheSPS receivers 330 and 370 may be connected to one or more antennas 336and 376, respectively, and may provide means for receiving and/ormeasuring SPS signals 338 and 378, respectively, such as globalpositioning system (GPS) signals, global navigation satellite system(GLONASS) signals, Galileo signals, Beidou signals, Indian RegionalNavigation Satellite System (NAVIC), Quasi-Zenith Satellite System(QZSS), etc. The SPS receivers 330 and 370 may comprise any suitablehardware and/or software for receiving and processing SPS signals 338and 378, respectively. The SPS receivers 330 and 370 request informationand operations as appropriate from the other systems, and performscalculations necessary to determine positions of the UE 302 and the basestation 304 using measurements obtained by any suitable SPS algorithm.

The base station 304 and the network entity 306 each include at leastone network interfaces 380 and 390, respectively, providing means forcommunicating (e.g., means for transmitting, means for receiving, etc.)with other network entities. For example, the network interfaces 380 and390 (e.g., one or more network access ports) may be configured tocommunicate with one or more network entities via a wire-based orwireless backhaul connection. In some aspects, the network interfaces380 and 390 may be implemented as transceivers configured to supportwire-based or wireless signal communication. This communication mayinvolve, for example, sending and receiving messages, parameters, and/orother types of information.

The UE 302, the base station 304, and the network entity 306 alsoinclude other components that may be used in conjunction with theoperations as disclosed herein. The UE 302 includes processor circuitryimplementing at least one processor 332 for providing functionalityrelating to, for example, wireless positioning, and for providing otherprocessing functionality. The base station 304 includes at at least oneprocessor 384 for providing functionality relating to, for example,wireless positioning as disclosed herein, and for providing otherprocessing functionality. The network entity 306 includes at least oneprocessor 394 for providing functionality relating to, for example,wireless positioning as disclosed herein, and for providing otherprocessing functionality. The processors 332, 384, and 394 may thereforeprovide means for processing, such as means for determining, means forcalculating, means for receiving, means for transmitting, means forindicating, etc. In an aspect, the processors 332, 384, and 394 mayinclude, for example, one or more processors, such as one or moregeneral purpose processors, multi-core processors, ASICs, digital signalprocessors (DSPs), field programmable gate arrays (FPGA), otherprogrammable logic devices or processing circuitry, or variouscombinations thereof.

The UE 302, the base station 304, and the network entity 306 includememory circuitry implementing memory components 340, 386, and 396 (e.g.,each including a memory device), respectively, for maintaininginformation (e.g., information indicative of reserved resources,thresholds, parameters, and so on). The memory components 340, 386, and396 may therefore provide means for storing, means for retrieving, meansfor maintaining, etc. In some cases, the UE 302, the base station 304,and the network entity 306 may include positioning components 342, 388,and 398, respectively. The positioning components 342, 388, and 398 maybe hardware circuits that are part of or coupled to the processors 332,384, and 394, respectively, that, when executed, cause the UE 302, thebase station 304, and the network entity 306 to perform thefunctionality described herein. In other aspects, the positioningcomponents 342, 388, and 398 may be external to the processors 332, 384,and 394 (e.g., part of a modem processing system, integrated withanother processing system, etc.). Alternatively, the positioningcomponents 342, 388, and 398 may be memory modules stored in the memorycomponents 340, 386, and 396, respectively, that, when executed by theprocessors 332, 384, and 394 (or a modem processing system, anotherprocessing system, etc.), cause the UE 302, the base station 304, andthe network entity 306 to perform the functionality described herein.FIG. 3A illustrates possible locations of the positioning component 342,which may be part of the at least one WWAN transceiver 310, the memorycomponent 340, the at least one processor 332, or any combinationthereof, or may be a standalone component. FIG. 3B illustrates possiblelocations of the positioning component 388, which may be part of the atleast one WWAN transceiver 350, the memory component 386, the at leastone processor 384, or any combination thereof, or may be a standalonecomponent. FIG. 3C illustrates possible locations of the positioningcomponent 398, which may be part of the at least one network interfaces390, the memory component 396, the at least one processor 394, or anycombination thereof, or may be a standalone component.

The UE 302 may include one or more sensors 344 coupled to the at leastone processor 332 to provide means for sensing or detecting movementand/or orientation information that is independent of motion dataderived from signals received by the at least one WWAN transceiver 310,the at least one short-range wireless transceiver 320, and/or the SPSreceiver 330. By way of example, the sensor(s) 344 may include anaccelerometer (e.g., a micro-electrical mechanical systems (MEMS)device), a gyroscope, a geomagnetic sensor (e.g., a compass), analtimeter (e.g., a barometric pressure altimeter), and/or any other typeof movement detection sensor. Moreover, the sensor(s) 344 may include aplurality of different types of devices and combine their outputs inorder to provide motion information. For example, the sensor(s) 344 mayuse a combination of a multi-axis accelerometer and orientation sensorsto provide the ability to compute positions in two-dimensional (2D)and/or three-dimensional (3D) coordinate systems.

In addition, the UE 302 includes a user interface 346 providing meansfor providing indications (e.g., audible and/or visual indications) to auser and/or for receiving user input (e.g., upon user actuation of asensing device such a keypad, a touch screen, a microphone, and so on).Although not shown, the base station 304 and the network entity 306 mayalso include user interfaces.

Referring to the at least one processor 384 in more detail, in thedownlink, IP packets from the network entity 306 may be provided to theat least one processor 384. The at least one processor 384 may implementfunctionality for an RRC layer, a packet data convergence protocol(PDCP) layer, a radio link control (RLC) layer, and a medium accesscontrol (MAC) layer. The at least one processor 384 may provide RRClayer functionality associated with broadcasting of system information(e.g., master information block (MIB), system information blocks(SIBs)), RRC connection control (e.g., RRC connection paging, RRCconnection establishment, RRC connection modification, and RRCconnection release), inter-RAT mobility, and measurement configurationfor UE measurement reporting; PDCP layer functionality associated withheader compression/decompression, security (ciphering, deciphering,integrity protection, integrity verification), and handover supportfunctions; RLC layer functionality associated with the transfer of upperlayer PDUs, error correction through automatic repeat request (ARQ),concatenation, segmentation, and reassembly of RLC service data units(SDUs), re-segmentation of RLC data PDUs, and reordering of RLC dataPDUs; and MAC layer functionality associated with mapping betweenlogical channels and transport channels, scheduling informationreporting, error correction, priority handling, and logical channelprioritization.

The transmitter 354 and the receiver 352 may implement Layer-1 (L1)functionality associated with various signal processing functions.Layer-1, which includes a physical (PHY) layer, may include errordetection on the transport channels, forward error correction (FEC)coding/decoding of the transport channels, interleaving, rate matching,mapping onto physical channels, modulation/demodulation of physicalchannels, and MIMO antenna processing. The transmitter 354 handlesmapping to signal constellations based on various modulation schemes(e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying(QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an orthogonalfrequency division multiplexing (OFDM) subcarrier, multiplexed with areference signal (e.g., pilot) in the time and/or frequency domain, andthen combined together using an inverse fast Fourier transform (IFFT) toproduce a physical channel carrying a time domain OFDM symbol stream.The OFDM symbol stream is spatially precoded to produce multiple spatialstreams. Channel estimates from a channel estimator may be used todetermine the coding and modulation scheme, as well as for spatialprocessing. The channel estimate may be derived from a reference signaland/or channel condition feedback transmitted by the UE 302. Eachspatial stream may then be provided to one or more different antennas356. The transmitter 354 may modulate an RF carrier with a respectivespatial stream for transmission.

At the UE 302, the receiver 312 receives a signal through its respectiveantenna(s) 316. The receiver 312 recovers information modulated onto anRF carrier and provides the information to the at least one processor332. The transmitter 314 and the receiver 312 implement Layer-1functionality associated with various signal processing functions. Thereceiver 312 may perform spatial processing on the information torecover any spatial streams destined for the UE 302. If multiple spatialstreams are destined for the UE 302, they may be combined by thereceiver 312 into a single OFDM symbol stream. The receiver 312 thenconverts the OFDM symbol stream from the time-domain to the frequencydomain using a fast Fourier transform (FFT). The frequency domain signalcomprises a separate OFDM symbol stream for each subcarrier of the OFDMsignal. The symbols on each subcarrier, and the reference signal, arerecovered and demodulated by determining the most likely signalconstellation points transmitted by the base station 304. These softdecisions may be based on channel estimates computed by a channelestimator. The soft decisions are then decoded and de-interleaved torecover the data and control signals that were originally transmitted bythe base station 304 on the physical channel. The data and controlsignals are then provided to the at least one processor 332, whichimplements Layer-3 (L3) and Layer-2 (L2) functionality.

In the uplink, the at least one processor 332 provides demultiplexingbetween transport and logical channels, packet reassembly, deciphering,header decompression, and control signal processing to recover IPpackets from the core network. The at least one processor 332 is alsoresponsible for error detection.

Similar to the functionality described in connection with the downlinktransmission by the base station 304, the at least one processor 332provides RRC layer functionality associated with system information(e.g., MIB, SIBs) acquisition, RRC connections, and measurementreporting; PDCP layer functionality associated with headercompression/decompression, and security (ciphering, deciphering,integrity protection, integrity verification); RLC layer functionalityassociated with the transfer of upper layer PDUs, error correctionthrough ARQ, concatenation, segmentation, and reassembly of RLC SDUs,re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; andMAC layer functionality associated with mapping between logical channelsand transport channels, multiplexing of MAC SDUs onto transport blocks(TBs), demultiplexing of MAC SDUs from TBs, scheduling informationreporting, error correction through hybrid automatic repeat request(HARM), priority handling, and logical channel prioritization.

Channel estimates derived by the channel estimator from a referencesignal or feedback transmitted by the base station 304 may be used bythe transmitter 314 to select the appropriate coding and modulationschemes, and to facilitate spatial processing. The spatial streamsgenerated by the transmitter 314 may be provided to different antenna(s)316. The transmitter 314 may modulate an RF carrier with a respectivespatial stream for transmission.

The uplink transmission is processed at the base station 304 in a mannersimilar to that described in connection with the receiver function atthe UE 302. The receiver 352 receives a signal through its respectiveantenna(s) 356. The receiver 352 recovers information modulated onto anRF carrier and provides the information to the at least one processor384.

In the uplink, the at least one processor 384 provides demultiplexingbetween transport and logical channels, packet reassembly, deciphering,header decompression, control signal processing to recover IP packetsfrom the UE 302. IP packets from the at least one processor 384 may beprovided to the core network. The at least one processor 384 is alsoresponsible for error detection.

For convenience, the UE 302, the base station 304, and/or the networkentity 306 are shown in FIGS. 3A to 3C as including various componentsthat may be configured according to the various examples describedherein. It will be appreciated, however, that the illustrated blocks mayhave different functionality in different designs.

The various components of the UE 302, the base station 304, and thenetwork entity 306 may communicate with each other over data buses 334,382, and 392, respectively. The components of FIGS. 3A to 3C may beimplemented in various ways. In some implementations, the components ofFIGS. 3A to 3C may be implemented in one or more circuits such as, forexample, one or more processors and/or one or more ASICs (which mayinclude one or more processors). Here, each circuit may use and/orincorporate at least one memory component for storing information orexecutable code used by the circuit to provide this functionality. Forexample, some or all of the functionality represented by blocks 310 to346 may be implemented by processor and memory component(s) of the UE302 (e.g., by execution of appropriate code and/or by appropriateconfiguration of processor components). Similarly, some or all of thefunctionality represented by blocks 350 to 388 may be implemented byprocessor and memory component(s) of the base station 304 (e.g., byexecution of appropriate code and/or by appropriate configuration ofprocessor components). Also, some or all of the functionalityrepresented by blocks 390 to 398 may be implemented by processor andmemory component(s) of the network entity 306 (e.g., by execution ofappropriate code and/or by appropriate configuration of processorcomponents). For simplicity, various operations, acts, and/or functionsare described herein as being performed “by a UE,” “by a base station,”“by a network entity,” etc. However, as will be appreciated, suchoperations, acts, and/or functions may actually be performed by specificcomponents or combinations of components of the UE 302, base station304, network entity 306, etc., such as the processors 332, 384, 394, thetransceivers 310, 320, 350, and 360, the memory components 340, 386, and396, the positioning components 342, 388, and 398, etc.

Various frame structures may be used to support downlink and uplinktransmissions between network nodes (e.g., base stations and UEs). FIG.4A is a diagram 400 illustrating an example of a downlink framestructure, according to aspects of the disclosure. FIG. 4B is a diagram430 illustrating an example of channels within the downlink framestructure, according to aspects of the disclosure. Other wirelesscommunications technologies may have different frame structures and/ordifferent channels.

LTE, and in some cases NR, utilizes OFDM on the downlink andsingle-carrier frequency division multiplexing (SC-FDM) on the uplink.Unlike LTE, however, NR has an option to use OFDM on the uplink as well.OFDM and SC-FDM partition the system bandwidth into multiple (K)orthogonal subcarriers, which are also commonly referred to as tones,bins, etc. Each subcarrier may be modulated with data. In general,modulation symbols are sent in the frequency domain with OFDM and in thetime domain with SC-FDM. The spacing between adjacent subcarriers may befixed, and the total number of subcarriers (K) may be dependent on thesystem bandwidth. For example, the spacing of the subcarriers may be 15kilohertz (kHz) and the minimum resource allocation (resource block) maybe 12 subcarriers (or 180 kHz). Consequently, the nominal FFT size maybe equal to 128, 256, 512, 1024, or 2048 for system bandwidth of 1.25,2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidthmay also be partitioned into subbands. For example, a subband may cover1.08 MHz (i.e., 6 resource blocks), and there may be 1, 2, 4, 8, or 16subbands for system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz,respectively.

LTE supports a single numerology (subcarrier spacing (SCS), symbollength, etc.). In contrast, NR may support multiple numerologies (μ),for example, subcarrier spacings of 15 kHz (μ=0), 30 kHz (μ=1), 60 kHz(μ=2), 120 kHz (μ=3), and 240 kHz (μ=4) or greater may be available. Ineach subcarrier spacing, there are 14 symbols per slot. For 15 kHz SCS(μ=0), there is one slot per subframe, 10 slots per frame, the slotduration is 1 millisecond (ms), the symbol duration is 66.7 microseconds(μs), and the maximum nominal system bandwidth (in MHz) with a 4K FFTsize is 50. For 30 kHz SCS (μ=1), there are two slots per subframe, 20slots per frame, the slot duration is 0.5 ms, the symbol duration is33.3 μs, and the maximum nominal system bandwidth (in MHz) with a 4K FFTsize is 100. For 60 kHz SCS (μ=2), there are four slots per subframe, 40slots per frame, the slot duration is 0.25 ms, the symbol duration is16.7 μs, and the maximum nominal system bandwidth (in MHz) with a 4K FFTsize is 200. For 120 kHz SCS (μ=3), there are eight slots per subframe,80 slots per frame, the slot duration is 0.125 ms, the symbol durationis 8.33 μs, and the maximum nominal system bandwidth (in MHz) with a 4KFFT size is 400. For 240 kHz SCS (μ=4), there are 16 slots per subframe,160 slots per frame, the slot duration is 0.0625 ms, the symbol durationis 4.17 μs, and the maximum nominal system bandwidth (in MHz) with a 4KFFT size is 800.

In the example of FIGS. 4A and 4B, a numerology of 15 kHz is used. Thus,in the time domain, a 10 ms frame is divided into 10 equally sizedsubframes of 1 ms each, and each subframe includes one time slot. InFIGS. 4A and 4B, time is represented horizontally (on the X axis) withtime increasing from left to right, while frequency is representedvertically (on the Y axis) with frequency increasing (or decreasing)from bottom to top.

A resource grid may be used to represent time slots, each time slotincluding one or more time-concurrent resource blocks (RBs) (alsoreferred to as physical RBs (PRBs)) in the frequency domain. Theresource grid is further divided into multiple resource elements (REs).An RE may correspond to one symbol length in the time domain and onesubcarrier in the frequency domain. In the numerology of FIGS. 4A and4B, for a normal cyclic prefix, an RB may contain 12 consecutivesubcarriers in the frequency domain and seven consecutive symbols in thetime domain, for a total of 84 REs. For an extended cyclic prefix, an RBmay contain 12 consecutive subcarriers in the frequency domain and sixconsecutive symbols in the time domain, for a total of 72 REs. Thenumber of bits carried by each RE depends on the modulation scheme.

Some of the REs carry downlink reference (pilot) signals (DL-RS). TheDL-RS may include PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, etc.FIG. 4A illustrates example locations of REs carrying PRS (labeled “R”).

A collection of resource elements (REs) that are used for transmissionof PRS is referred to as a “PRS resource.” The collection of resourceelements can span multiple PRBs in the frequency domain and ‘N’ (such as1 or more) consecutive symbol(s) within a slot in the time domain. In agiven OFDM symbol in the time domain, a PRS resource occupiesconsecutive PRBs in the frequency domain.

The transmission of a PRS resource within a given PRB has a particularcomb size (also referred to as the “comb density”). A comb size ‘N’represents the subcarrier spacing (or frequency/tone spacing) withineach symbol of a PRS resource configuration. Specifically, for a combsize ‘N,’ PRS are transmitted in every Nth subcarrier of a symbol of aPRB. For example, for comb-4, for each symbol of the PRS resourceconfiguration, REs corresponding to every fourth subcarrier (such assubcarriers 0, 4, 8) are used to transmit PRS of the PRS resource.Currently, comb sizes of comb-2, comb-4, comb-6, and comb-12 aresupported for DL-PRS. FIG. 4A illustrates an example PRS resourceconfiguration for comb-6 (which spans six symbols). That is, thelocations of the shaded REs (labeled “R”) indicate a comb-6 PRS resourceconfiguration.

Currently, a DL-PRS resource may span 2, 4, 6, or 12 consecutive symbolswithin a slot with a fully frequency-domain staggered pattern. A DL-PRSresource can be configured in any higher layer configured downlink orflexible (FL) symbol of a slot. There may be a constant energy perresource element (EPRE) for all REs of a given DL-PRS resource. Thefollowing are the frequency offsets from symbol to symbol for comb sizes2, 4, 6, and 12 over 2, 4, 6, and 12 symbols. 2-symbol comb-2: {0, 1};4-symbol comb-2: {0, 1, 0, 1}; 6-symbol comb-2: {0, 1, 0, 1, 0, 1};12-symbol comb-2: {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}; 4-symbol comb-4:{0, 2, 1, 3}; 12-symbol comb-4: {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3};6-symbol comb-6: {0, 3, 1, 4, 2, 5}; 12-symbol comb-6: {0, 3, 1, 4, 2,5, 0, 3, 1, 4, 2, 5}; and 12-symbol comb-12: {0, 6, 3, 9, 1, 7, 4, 10,2, 8, 5, 11}.

A “PRS resource set” is a set of PRS resources used for the transmissionof PRS signals, where each PRS resource has a PRS resource ID. Inaddition, the PRS resources in a PRS resource set are associated withthe same TRP. A PRS resource set is identified by a PRS resource set IDand is associated with a particular TRP (identified by a TRP ID). Inaddition, the PRS resources in a PRS resource set have the sameperiodicity, a common muting pattern configuration, and the samerepetition factor (such as “PRS-ResourceRepetitionFactor”) across slots.The periodicity is the time from the first repetition of the first PRSresource of a first PRS instance to the same first repetition of thesame first PRS resource of the next PRS instance. The periodicity mayhave a length selected from 2{circumflex over ( )}μ*{4, 5, 8, 10, 16,20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots, withμ=0, 1, 2, 3. The repetition factor may have a length selected from {1,2, 4, 6, 8, 16, 32} slots.

A PRS resource ID in a PRS resource set is associated with a single beam(or beam ID) transmitted from a single TRP (where a TRP may transmit oneor more beams). That is, each PRS resource of a PRS resource set may betransmitted on a different beam, and as such, a “PRS resource,” orsimply “resource,” also can be referred to as a “beam.” Note that thisdoes not have any implications on whether the TRPs and the beams onwhich PRS are transmitted are known to the UE.

A “PRS instance” or “PRS occasion” is one instance of a periodicallyrepeated time window (such as a group of one or more consecutive slots)where PRS are expected to be transmitted. A PRS occasion also may bereferred to as a “PRS positioning occasion,” a “PRS positioninginstance, a “positioning occasion,” “a positioning instance,” a“positioning repetition,” or simply an “occasion,” an “instance,” or a“repetition.”

A “positioning frequency layer” (also referred to simply as a “frequencylayer”) is a collection of one or more PRS resource sets across one ormore TRPs that have the same values for certain parameters.Specifically, the collection of PRS resource sets has the samesubcarrier spacing and cyclic prefix (CP) type (meaning all numerologiessupported for the PDSCH are also supported for PRS), the same Point A,the same value of the downlink PRS bandwidth, the same start PRB (andcenter frequency), and the same comb-size. The Point A parameter takesthe value of the parameter “ARFCN-ValueNR” (where “ARFCN” stands for“absolute radio-frequency channel number”) and is an identifier/codethat specifies a pair of physical radio channel used for transmissionand reception. The downlink PRS bandwidth may have a granularity of fourPRBs, with a minimum of 24 PRBs and a maximum of 272 PRBs. Currently, upto four frequency layers have been defined, and up to two PRS resourcesets may be configured per TRP per frequency layer.

The concept of a frequency layer is somewhat like the concept ofcomponent carriers and bandwidth parts (BWPs), but different in thatcomponent carriers and BWPs are used by one base station (or a macrocell base station and a small cell base station) to transmit datachannels, while frequency layers are used by several (usually three ormore) base stations to transmit PRS. A UE may indicate the number offrequency layers it can support when it sends the network itspositioning capabilities, such as during an LTE positioning protocol(LPP) session. For example, a UE may indicate whether it can support oneor four positioning frequency layers.

Note that the terms “positioning reference signal” and “PRS” generallyrefer to specific reference signals that are used for positioning in NRand LTE systems. However, as used herein, the terms “positioningreference signal” and “PRS” may also refer to any type of referencesignal that can be used for positioning, such as but not limited to, PRSas defined in LTE and NR, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB,SRS, UL-PRS, etc. In addition, the terms “positioning reference signal”and “PRS” may refer to downlink or uplink positioning reference signals,unless otherwise indicated by the context. If needed to furtherdistinguish the type of PRS, a downlink positioning reference signal maybe referred to as a “DL-PRS,” and an uplink positioning reference signal(e.g., an SRS-for-positioning, PTRS) may be referred to as an “UL-PRS.”In addition, for signals that may be transmitted in both the uplink anddownlink (e.g., DMRS, PTRS), the signals may be prepended with “UL” or“DL” to distinguish the direction. For example, “UL-DMRS” may bedifferentiated from “DL-DMRS.”

PRS, and other types of positioning reference signals, are used for anumber of cellular network-based positioning technologies, includingdownlink-based, uplink-based, and downlink-and-uplink-based positioningmethods. Downlink-based positioning methods include observed timedifference of arrival (OTDOA) in LTE, downlink time difference ofarrival (DL-TDOA) in NR, and downlink angle-of-departure (DL-AoD) in NR.In an OTDOA or DL-TDOA positioning procedure, a UE measures thedifferences between the times of arrival (ToAs) of reference signals(e.g., PRS, TRS, CSI-RS, SSB, etc.) received from pairs of basestations, referred to as reference signal time difference (RSTD) or timedifference of arrival (TDOA) measurements, and reports them to apositioning entity. More specifically, the UE receives the identifiers(IDs) of a reference base station (e.g., a serving base station) andmultiple non-reference base stations in assistance data. The UE thenmeasures the RSTD between the reference base station and each of thenon-reference base stations. Based on the known locations of theinvolved base stations and the RSTD measurements, the positioning entitycan estimate the UE's location.

For DL-AoD positioning, the positioning entity uses a beam report fromthe UE of received signal strength measurements of multiple downlinktransmit beams to determine the angle(s) between the UE and thetransmitting base station(s). The positioning entity can then estimatethe location of the UE based on the determined angle(s) and the knownlocation(s) of the transmitting base station(s).

Uplink-based positioning methods include uplink time difference ofarrival (UL-TDOA) and uplink angle-of-arrival (UL-AoA). UL-TDOA issimilar to DL-TDOA, but is based on uplink reference signals (e.g., SRS)transmitted by the UE. For UL-AoA positioning, one or more base stationsmeasure the received signal strength of one or more uplink referencesignals (e.g., SRS) received from a UE on one or more uplink receivebeams. The positioning entity uses the signal strength measurements andthe angle(s) of the receive beam(s) to determine the angle(s) betweenthe UE and the base station(s). Based on the determined angle(s) and theknown location(s) of the base station(s), the positioning entity canthen estimate the location of the UE.

Downlink-and-uplink-based positioning methods include enhanced cell-ID(E-CID) positioning and multi-round-trip-time (RTT) positioning (alsoreferred to as “multi-cell RTT”). In an RTT procedure, an initiator (abase station or a UE) transmits an RTT measurement signal (e.g., a PRSor SRS) to a responder (a UE or base station), which transmits an RTTresponse signal (e.g., an SRS or PRS) back to the initiator. The RTTresponse signal includes the difference between the ToA of the RTTmeasurement signal and the transmission time of the RTT response signal,referred to as the reception-to-transmission (Rx-Tx) time difference.The initiator calculates the difference between the transmission time ofthe RTT measurement signal and the ToA of the RTT response signal,referred to as the transmission-to-reception (Tx-Rx) time difference.The propagation time (also referred to as the “time of flight”) betweenthe initiator and the responder can be calculated from the Tx-Rx andRx-Tx time differences. Based on the propagation time and the knownspeed of light, the distance between the initiator and the responder canbe determined. For multi-RTT positioning, a UE performs an RTT procedurewith multiple base stations to enable its location to be triangulatedbased on the known locations of the base stations. RTT and multi-RTTmethods can be combined with other positioning techniques, such asUL-AoA and DL-AoD, to improve location accuracy.

The E-CID positioning method is based on radio resource management (RRM)measurements. In E-CID, the UE reports the serving cell ID, the timingadvance (TA), and the identifiers, estimated timing, and signal strengthof detected neighbor base stations. The location of the UE is thenestimated based on this information and the known locations of the basestation(s).

To assist positioning operations, a location server (e.g., locationserver 230, LMF 270, SLP 272) may provide assistance data to the UE. Forexample, the assistance data may include identifiers of the basestations (or the cells/TRPs of the base stations) from which to measurereference signals, the reference signal configuration parameters (e.g.,the number of consecutive positioning subframes, periodicity ofpositioning subframes, muting sequence, frequency hopping sequence,reference signal identifier, reference signal bandwidth, etc.), and/orother parameters applicable to the particular positioning method.Alternatively, the assistance data may originate directly from the basestations themselves (e.g., in periodically broadcasted overheadmessages, etc.). in some cases, the UE may be able to detect neighbornetwork nodes itself without the use of assistance data.

In the case of an OTDOA or DL-TDOA positioning procedure, the assistancedata may further include an expected RSTD value and an associateduncertainty, or search window, around the expected RSTD. In some cases,the value range of the expected RSTD may be +/−500 microseconds (μs). Insome cases, when any of the resources used for the positioningmeasurement are in FR1, the value range for the uncertainty of theexpected RSTD may be +/−32 μs. In other cases, when all of the resourcesused for the positioning measurement(s) are in FR2, the value range forthe uncertainty of the expected RSTD may be +/−8 μs.

A location estimate may be referred to by other names, such as aposition estimate, location, position, position fix, fix, or the like. Alocation estimate may be geodetic and comprise coordinates (e.g.,latitude, longitude, and possibly altitude) or may be civic and comprisea street address, postal address, or some other verbal description of alocation. A location estimate may further be defined relative to someother known location or defined in absolute terms (e.g., using latitude,longitude, and possibly altitude). A location estimate may include anexpected error or uncertainty (e.g., by including an area or volumewithin which the location is expected to be included with some specifiedor default level of confidence).

The downlink PRS transmitted for the above-described positioningprocedures can be transmitted periodically or on demand. “On demand” PRStransmission means that PRS are only transmitted when there is a requestfor PRS to be transmitted, as opposed to TRPs in the networkperiodically transmitting PRS regardless of whether there are anyongoing positioning sessions. The on demand PRS may themselves beperiodic within a predefined time period (e.g., during the positioningsession), semi-persistent, or aperiodic. As will be appreciated, the useof on demand PRS transmission reduces PRS overhead. In some cases, ondemand PRS transmission may be requested by a UE, such as for a UE-basedpositioning procedure (in which the UE estimates its own location) or aUE-requested positioning procedure (in which the UE requests the networkto estimate the UE's location). The UE may send a request to receiveDL-PRS from and/or transmit UL-PRS to each base station involved in thepositioning procedure, or send the request to its serving base stationor the location server, which then forwards the request to the involvedbase stations. In other cases, on demand PRS transmission may berequested by the network (e.g., location server 230, LMF 270, SLP 272),such as for a UE-assisted positioning procedure (in which the networkestimates the UE's location, either of its own initiative or on requestfrom the UE or another entity). In this case, the location server cansend the request to the involved base stations.

Network operators may cover a geographic area by deploying an “anchor”set of base stations (e.g., eNBs, ng-eNBs, gNBs) over the whole area inone frequency band, and additional base stations (e.g., ng-eNBS, gNBs)over subsets of the geographic area in one or more other frequencybands. For example, the additional base stations may have morecapabilities than the anchor set of base stations, and the networkoperator may gradually phase them in based on market needs.

The present disclosure provides techniques for using a first frequency“band” for periodically broadcasted PRS and one or more additionalfrequency “bands” for on-demand PRS. More specifically, during a givenpositioning procedure, a UE may receive periodic PRS in one band and ondemand PRS in one or more other bands. Note that the term “band,” asused herein, refers to some generic block of frequency, such as afrequency range (e.g., FR1, FR2, etc.), a frequency band within afrequency range, a component carrier, or a positioning frequency layer.As such, periodic PRS would be transmitted in a first frequency range, afirst frequency band, a first component carrier, or a first frequencylayer, and on demand PRS would be transmitted in one or more differentfrequency ranges, one or more different frequency bands, one or moredifferent component carriers, or one or more different frequency layers.

A UE can indicate its capability to operate on multiple bands, and thelocation server (e.g., location server 230, LMF 270, SLP 272) mayconfigure assistance information for those bands. For UE-basedpositioning, the assistance information may include the locations of theinvolved base stations (i.e., the base stations configured to transmitPRS to the UE), from which the UE may infer differences in deploymentdensities across bands (i.e., the bands on which it is capable ofoperating). That is, since the UE receives the locations of the involvedbase stations and the bands they use for transmitting PRS, the UE candetermine the number and geographic distribution of the base stationstransmitting PRS on each band.

For UE-assisted positioning, the locations of the base stations are notincluded in the assistance information. However, the UE may infer theirlocations based on a PRS search in the bands it can support. Forexample, the UE may detect more PRS in a first band in which it canoperate than in a second band. Alternatively, the assistance informationmay include coarse level locations of the involved base stations. Forexample, the assistance information may indicate that there are morebase stations operating in a first band compared to a second band.Whether for UE-based or UE-assisted positioning, the PRS configurationreceived from the location server may indicate that on demand PRS isonly supported in certain bands.

For on demand PRS transmission, the UE can send a PRS request (i.e., arequest to transmit UL-PRS or receive DL-PRS) to the base stationsinvolved in the positioning procedure via RRC signaling, MAC controlelements (MAC-CEs), or uplink control information (UCI). Alternatively,the UE may send a PRS request to its serving base station or thelocation server (e.g., location server 230, LMF 270, SLP 272)identifying the base stations from which it wants to receive PRS. Inturn, the location server (or serving base station) can forward therequest to the identified base stations. Where the location server islocated in the core network (e.g., 5GC 210, 5GC 260), the UE can sendthe request via RRC signaling or LPP signaling. Where the locationserver is located in the RAN (e.g., NG-RAN 220), such as where thelocation server is co-located with one or more base stations, the UE maysend the request using either UE-to-base station signaling or UE-to-corenetwork signaling (e.g., RRC).

Where the UE sends a PRS request to each involved base station, the band(e.g., frequency range, component carrier, BWP, frequency layer, etc.)on which the request is conveyed from the UE to the base station mayindicate the band on which the on demand PRS should be transmitted.Thus, for example, if a request is transmitted in FR2, it indicates thatthe base station should transmit PRS in FR2. Likewise, if a request istransmitted on a particular component carrier, it indicates that thebase station should transmit PRS on that component carrier. If therequest is transmitted in a particular BWP, it indicates that the basestation should transmit PRS on the frequency layer corresponding to thatBWP.

Alternatively, the PRS request can include a band identifier. Forexample, based on the UE's knowledge of the deployment density of basestations in different bands, as described above, the UE can indicate oneor more preferred bands for the on demand PRS.

Thus, during a given positioning procedure, a UE may receive periodicPRS in one band, and in addition, receive on demand PRS in one or moreother bands (whether requested by the UE or the locations server). In anaspect, the on demand PRS may be used to supplement the periodic PRS.More specifically, in addition to the periodic PRS a UE may bemeasuring, the UE can request on demand PRS from a specific base station(or a specific set of base stations) based on its positioning needs. Forexample, the UE may request PRS from one or more base stations ofspecific heights in order to compute a 3D location. This may be based onthe UE's prior height estimate (e.g., from its barometer) and may berequested to achieve good (e.g., above a threshold) geometric dilutionof precision (GDOP). (GDOP specifies error propagation as a mathematicaleffect of navigation satellite geometry on positional measurementprecision.) In this way, the UE can calculate a 2D estimate of itslocation using periodic PRS from a first set of base stations operatingin a first band, and calculate a 3D estimate of its location byincorporating measurements of on demand PRS from one or more sets ofbase stations operating in one or more other bands.

As another example, a UE may be measuring periodic PRS from a first setof base stations operating in a first band that are all located to oneor two sides of the UE. To improve the resulting location estimate, theUE may identify one or more base stations operating in one or more otherbands that are on an opposite side of the UE from the first set of basestations, and request on demand PRS from those base stations. In thatway, the UE will receive and measure PRS from base stations surroundingthe UE. As will be appreciated, measuring PRS from base stations thatsurround the UE will provide a better location estimate of the UE thanwill measuring PRS from base stations that are only on one or two sidesof the UE.

In an aspect, a UE may request on-demand PRS in a second band afterdetermining that it cannot receive/measure the periodic PRS transmittedin a first band.

Upon measuring the on demand (and periodic) PRS on the first (andsecond) bands, the UE may report/send the measurements to a positioningentity. For UE-based positioning, the positioning entity may be apositioning engine on the UE (e.g., positioning component 342). ForUE-assisted positioning, the positioning entity may be a location server(e.g., location server 230, LMF 270, SLP 272), a positioning engine atthe serving base station, a third-party server or application, or thelike. The measurements can be reported separately or in the samemeasurement report, depending on various factors. The factors mayinclude, for example, the report configuration (whether the UE isconfigured to consolidate the measurements into one report or sendindependent reports), the periodicity of the on demand and periodic PRS,the measurement requirements (e.g., RSTD based on PRS from two separatepositioning frequency layers), and/or the like.

For downlink-and-uplink-based positioning sessions (e.g., RTT), the UEmay transmit SRS in response to reception of PRS. In general, the ondemand PRS on the second band depends on the positioning method beingperformed on the first band. For example, if an RTT positioningprocedure is being performed on the first band, then it would to be ondemand RTT (meaning both downlink and uplink PRS) on the second band.Because the periodic SRS and the on demand SRS are located on twodifferent bands, the UE will likely not be able to transmit them at thesame time. Therefore, the UE may only transmit the on demand group.However, the Rx-Tx time difference measurement for the RTT positioningprocedure on both bands could be consolidated into one report.

Accordingly, for positioning involving SRS, the general procedure is thesame. That is, the UE requests the location server for on demand PRS andthe location server configures the requested PRS. For DL-PRS, the ondemand configuration is received from the location server via LPP,whereas for SRS, the configuration is received from the serving cell.The location server will coordinate the PRS transmission and receptionacross the involved gNB s.

FIG. 5 is an example call flow 500 between a UE 504 (e.g., any of theUEs described herein), a serving base station (BS) 502 (e.g., any of thebase stations described herein), and a location server 570 (e.g.,location server 230, LMF 270, SLP 272), according to aspects of thedisclosure.

At stage 505, the UE 504 sends a request for on demand PRS to thelocation server 570. At 510, the location server 570 identifies/selectscandidate sources (e.g., base stations) to transmit on demand PRS. Thecandidate sources may be selected based on their GDOP relative to the UE504, their availability to transmit on demand PRS, and/or the like. At515, the location server sends an on demand PRS configuration andscheduling to the base station 502. At 520, the location server 570 orthe base station 502 sends the on demand PRS configuration andscheduling to the UE 504. At 525, the location server 570 or the basestation 502 triggers the UE 504 to measure and report the on demand PRS.At 530, the base station 502 transmits on demand PRS to the UE 504, ifthe base station 502 is one of the on demand PRS sources. At 535, the UE504 measures the on demand PRS received from the on demand PRS sources,as well as the periodic PRS if available. At 540, for UE-assistedpositioning, the UE 504 reports the measurements of the on demand andperiodic PRS to the location server 570. Alternatively, for UE-basedpositioning, the UE 504 would calculate an estimate of its location (notshown).

FIG. 6 illustrates an example method 600 of wireless communication,according to aspects of the disclosure. In an aspect, the method 600 maybe performed by a UE, such as any of the UEs described herein.

At 610, the UE transmits a first request for a first set of basestations to transmit first on demand PRS in a first band. In an aspect,operation 610 may be performed by the at least one WWAN transceiver 310,the at least one processor 332, memory component 340, and/or positioningcomponent 342, any or all of which may be considered means forperforming this operation.

At 620, the UE measures the first on demand PRS from the first set ofbase stations in the first band. In an aspect, operation 620 may beperformed by the at least one WWAN transceiver 310, the at least oneprocessor 332, memory component 340, and/or positioning component 342,any or all of which may be considered means for performing thisoperation.

At 630, the UE measures periodic PRS from a second set of base stationsoperating in a second band (different from the first band). In anaspect, operation 630 may be performed by the at least one WWANtransceiver 310, the at least one processor 332, memory component 340,and/or positioning component 342, any or all of which may be consideredmeans for performing this operation.

At 640, the UE sends, to a positioning entity (e.g., a positioningengine at the UE (e.g., positioning component 342), a location server, aserving base station), positioning measurements (e.g., ToAs, RSTDs,etc.) of at least the first on demand PRS and the periodic PRS. In anaspect, operation 640 may be performed by the at least one WWANtransceiver 310, the at least one processor 332, memory component 340,and/or positioning component 342, any or all of which may be consideredmeans for performing this operation.

As will be appreciated, technical advantages of the method 600 includeenabling a UE to measure more PRS from more base stations, therebyimproving positioning performance, reducing the use of system resources,permitting the reuse of other (non-on demand) bands, and reducing powerconsumption (as the on demand PRS may be transmitted in a band with lesspower efficiency).

In the detailed description above it can be seen that different featuresare grouped together in examples. This manner of disclosure should notbe understood as an intention that the example clauses have morefeatures than are explicitly mentioned in each clause. Rather, thevarious aspects of the disclosure may include fewer than all features ofan individual example clause disclosed. Therefore, the following clausesshould hereby be deemed to be incorporated in the description, whereineach clause by itself can stand as a separate example. Although eachdependent clause can refer in the clauses to a specific combination withone of the other clauses, the aspect(s) of that dependent clause are notlimited to the specific combination. It will be appreciated that otherexample clauses can also include a combination of the dependent clauseaspect(s) with the subject matter of any other dependent clause orindependent clause or a combination of any feature with other dependentand independent clauses. The various aspects disclosed herein expresslyinclude these combinations, unless it is explicitly expressed or can bereadily inferred that a specific combination is not intended (e.g.,contradictory aspects, such as defining an element as both an insulatorand a conductor). Furthermore, it is also intended that aspects of aclause can be included in any other independent clause, even if theclause is not directly dependent on the independent clause.

Implementation examples are described in the following numbered clauses:

Clause 1. A method of wireless communication performed by a userequipment (UE), comprising: transmitting a first request for a first setof base stations to transmit first on demand positioning referencesignals (PRS) in a first band; measuring the first on demand PRS fromthe first set of base stations in the first band; measuring periodic PRSfrom a second set of base stations operating in a second band; andenabling a positioning entity to calculate a location of the UE based onpositioning measurements of at least the first on demand PRS and theperiodic PRS.

Clause 2. The method of clause 1, further comprising: transmitting, to alocation server, a capability message indicating that the UE can supportoperation on at least the first band and the second band.

Clause 3. The method of clause 2, further comprising: receiving, fromthe location server, assistance information for at least the first setof base stations and the second set of base stations.

Clause 4. The method of clause 3, wherein the assistance informationincludes locations of at least the first set of base stations and thesecond set of base stations.

Clause 5. The method of any of clauses 3 to 4, wherein the assistanceinformation indicates at least a number of the first set of basestations operating in the first band and a number of the second set ofbase stations operating in the second band.

Clause 6. The method of any of clauses 1 to 5, further comprising:determining at least a number of the first set of base stationsoperating in the first band and a number of the second set of basestations operating in the second band based on detecting at least thefirst on demand PRS and the periodic PRS.

Clause 7. The method of clause 6, further comprising: determining anumber of a third set of base stations capable of transmitting second ondemand PRS in a third band.

Clause 8. The method of clause 7, wherein the UE transmits the firstrequest to the first set of base stations based on the number of thefirst set of base stations compared to the number of the third set ofbase stations.

Clause 9. The method of any of clauses 1 to 8, further comprising:receiving an indication that only the first band supports on demand PRS.

Clause 10. The method of any of clauses 1 to 9, wherein: the firstrequest is transmitted on the first band, and the first request beingtransmitted on the first band indicates that the first request is forthe first set of base stations to transmit the first on demand PRS inthe first band.

Clause 11. The method of any of clauses 1 to 10, wherein the firstrequest includes an identifier of the first band.

Clause 12. The method of any of clauses 1 to 11, wherein the UEtransmits the first request for the first set of base stations totransmit the first on demand PRS in the first band based on apositioning need not satisfied by the periodic PRS transmitted by thesecond set of base stations.

Clause 13. The method of any of clauses 1 to 12, further comprising:transmitting a second request for a third set of base stations totransmit second on demand PRS in a third band; and measuring the secondon demand PRS from the third set of base stations in the third band,wherein enabling the positioning entity to calculate the location of theUE is further based on positioning measurements of the second on demandPRS.

Clause 14. The method of any of clauses 1 to 13, wherein the UEtransmits the first request to each of the first set of base stations.

Clause 15. The method of any of clauses 1 to 14, wherein: the UEtransmits the first request to a location server or a serving basestation, and the first request is forwarded by the location server orthe serving base station to each of the first set of base stations.

Clause 16. The method of any of clauses 1 to 15, wherein: the first bandcomprises a first frequency range, a first frequency band, a firstcomponent carrier, or a first positioning frequency layer, and thesecond band comprises a second frequency range, a second frequency band,a second component carrier, or a second positioning frequency layer.

Clause 17. The method of any of clauses 1 to 16, wherein: thepositioning entity comprises the UE, and enabling the positioning entityto calculate the location of the UE comprises the UE calculating thelocation of the UE based on the positioning measurements of at least thefirst on demand PRS and the periodic PRS.

Clause 18. The method of any of clauses 1 to 17, wherein: thepositioning entity comprises a location server, or a serving basestation, and enabling the positioning entity to calculate the locationof the UE comprises the UE transmitting the positioning measurements ofat least the first on demand PRS and the periodic PRS to the positioningentity.

Clause 19. An apparatus comprising a memory and at least one processorcommunicatively coupled to the memory, the memory and the at least oneprocessor configured to perform a method according to any of clauses 1to 18.

Clause 20. An apparatus comprising means for performing a methodaccording to any of clauses 1 to 18.

Clause 21. A non-transitory computer-readable medium storingcomputer-executable instructions, the computer-executable comprising atleast one instruction for causing a computer or processor to perform amethod according to any of clauses 1 to 18.

Additional implementation examples are described in the followingnumbered clauses:

Clause 1. A method of wireless communication performed by a userequipment (UE), comprising: transmitting a first request for a first setof base stations to transmit first on demand positioning referencesignals (PRS) in a first band; measuring the first on demand PRS fromthe first set of base stations in the first band; measuring periodic PRSfrom a second set of base stations operating in a second band; andsending, to a positioning entity, positioning measurements of at leastthe first on demand PRS and the periodic PRS.

Clause 2. The method of clause 1, further comprising: transmitting, to alocation server, a capability message indicating that the UE can supportoperation on at least the first band and the second band.

Clause 3. The method of clause 2, further comprising: receiving, fromthe location server, assistance information for at least the first setof base stations and the second set of base stations.

Clause 4. The method of clause 3, wherein the assistance informationincludes locations of at least the first set of base stations and thesecond set of base stations.

Clause 5. The method of any of clauses 3 to 4, wherein the assistanceinformation indicates at least a number of the first set of basestations operating in the first band and a number of the second set ofbase stations operating in the second band.

Clause 6. The method of any of clauses 1 to 5, further comprising:determining at least a number of the first set of base stationsoperating in the first band and a number of the second set of basestations operating in the second band based on detecting at least thefirst on demand PRS and the periodic PRS.

Clause 7. The method of clause 6, further comprising: determining anumber of a third set of base stations capable of transmitting second ondemand PRS in a third band.

Clause 8. The method of clause 7, wherein the UE transmits the firstrequest to the first set of base stations based on the number of thefirst set of base stations compared to the number of the third set ofbase stations.

Clause 9. The method of any of clauses 1 to 8, further comprising:receiving an indication that only the first band supports on demand PRS.

Clause 10. The method of any of clauses 1 to 9, wherein: the firstrequest is transmitted on the first band, and the first request beingtransmitted on the first band indicates that the first request is forthe first set of base stations to transmit the first on demand PRS inthe first band.

Clause 11. The method of any of clauses 1 to 9, wherein the firstrequest is transmitted on the second band.

Clause 12. The method of any of clauses 1 to 11, wherein the firstrequest includes an identifier of the first band.

Clause 13. The method of any of clauses 1 to 12, wherein the UEtransmits the first request for the first set of base stations totransmit the first on demand PRS in the first band based on apositioning need not satisfied by the periodic PRS transmitted by thesecond set of base stations.

Clause 14. The method of clause 13, wherein the positioning need isbased on a geometric dilution of precision (GDOP) threshold.

Clause 15. The method of any of clauses 1 to 14, further comprising:transmitting a second request for a third set of base stations totransmit second on demand PRS in a third band; measuring the second ondemand PRS from the third set of base stations in the third band; andsending, to the positioning entity, positioning measurements of thesecond on demand PRS.

Clause 16. The method of any of clauses 1 to 15, wherein the UEtransmits the first request to each of the first set of base stations.

Clause 17. The method of any of clauses 1 to 15, wherein: the UEtransmits the first request to a location server or a serving basestation, and the first request is sent by the location server or theserving base station to each of the first set of base stations.

Clause 18. The method of any of clauses 1 to 17, wherein: the first bandcomprises a first frequency range, a first frequency band, a firstcomponent carrier, or a first positioning frequency layer, and thesecond band comprises a second frequency range, a second frequency band,a second component carrier, or a second positioning frequency layer.

Clause 19. The method of any of clauses 1 to 18, wherein: thepositioning entity comprises a positioning engine at the UE, and themethod further comprises calculating a location of the UE based on thepositioning measurements of at least the first on demand PRS and theperiodic PRS.

Clause 20. The method of any of clauses 1 to 18, wherein the positioningentity comprises a location server or a serving base station.

Clause 21. An apparatus comprising a memory and at least one processorcommunicatively coupled to the memory, the memory and the at least oneprocessor configured to perform a method according to any of clauses 1to 20.

Clause 22. An apparatus comprising means for performing a methodaccording to any of clauses 1 to 20.

Clause 23. A non-transitory computer-readable medium storingcomputer-executable instructions, the computer-executable comprising atleast one instruction for causing a computer or processor to perform amethod according to any of clauses 1 to 20.

Those of skill in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those of skill in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted as causing adeparture from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an ASIC, a field-programmable gate array (FPGA), or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,for example, a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The methods, sequences and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in random access memory (RAM), flashmemory, read-only memory (ROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), registers, hard disk, aremovable disk, a CD-ROM, or any other form of storage medium known inthe art. An example storage medium is coupled to the processor such thatthe processor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor. The processor and the storage medium may reside in anASIC. The ASIC may reside in a user terminal (e.g., UE). In thealternative, the processor and the storage medium may reside as discretecomponents in a user terminal.

In one or more example aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Computer-readable media includes both computerstorage media and communication media including any medium thatfacilitates transfer of a computer program from one place to another. Astorage media may be any available media that can be accessed by acomputer. By way of example, and not limitation, such computer-readablemedia can comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium that can be used to carry or store desired program code inthe form of instructions or data structures and that can be accessed bya computer. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

While the foregoing disclosure shows illustrative aspects of thedisclosure, it should be noted that various changes and modificationscould be made herein without departing from the scope of the disclosureas defined by the appended claims. The functions, steps and/or actionsof the method claims in accordance with the aspects of the disclosuredescribed herein need not be performed in any particular order.Furthermore, although elements of the disclosure may be described orclaimed in the singular, the plural is contemplated unless limitation tothe singular is explicitly stated.

What is claimed is:
 1. A method of wireless communication performed by auser equipment (UE), comprising: transmitting, during a positioningsession, a first request for transmission of first on demand positioningreference signals (PRS) in a first band; measuring, during thepositioning session, the first on demand PRS in the first band;measuring, during the positioning session, periodic PRS transmitted in asecond band different from the first band, wherein transmitting thefirst request for the transmission of the first on demand PRS in thefirst band and measuring the periodic PRS transmitted in the second bandare based on positioning requirements of the positioning session; andsending, to a positioning entity, positioning measurements of at leastthe first on demand PRS and the periodic PRS.
 2. The method of claim 1,further comprising: transmitting, to a location server, a capabilitymessage indicating that the UE can support operation on at least thefirst band and the second band.
 3. The method of claim 1, wherein: thefirst on demand PRS are transmitted by a first set of base stations, andthe periodic PRS are transmitted by a second set of base stations. 4.The method of claim 3, wherein: the first set of base stations is thesame as the second set of base stations, or the first set of basestations is different from the second set of base stations.
 5. Themethod of claim 3, further comprising: receiving, from the locationserver, assistance information for at least the first set of basestations and the second set of base stations.
 6. The method of claim 5,wherein the assistance information includes locations of at least thefirst set of base stations and the second set of base stations.
 7. Themethod of claim 5, wherein the assistance information indicates at leasta number of the first set of base stations operating in the first bandand a number of the second set of base stations operating in the secondband.
 8. The method of claim 3, further comprising: determining at leasta number of the first set of base stations operating in the first bandand a number of the second set of base stations operating in the secondband based on detecting at least the first on demand PRS and theperiodic PRS.
 9. The method of claim 1, further comprising: receiving anindication that only the first band supports on demand PRS.
 10. Themethod of claim 1, wherein: the first request is transmitted on thefirst band, and the first request being transmitted on the first bandindicates that the first request is for the first on demand PRS to betransmitted in the first band.
 11. The method of claim 1, wherein thefirst request is transmitted on the second band.
 12. The method of claim1, wherein the first request includes an identifier of the first band.13. The method of claim 1, wherein transmitting the first request forthe transmission of the first on demand PRS in the first band andmeasuring the periodic PRS transmitted in the second band being based onthe positioning requirements of the positioning session comprisestransmitting the first request for the transmission of the first ondemand PRS in the first band and measuring the periodic PRS transmittedin the second band based on a positioning need not satisfied by theperiodic PRS transmitted in the second band.
 14. The method of claim 13,wherein the positioning need is based on a geometric dilution ofprecision (GDOP) threshold.
 15. The method of claim 1, furthercomprising: transmitting a second request for transmission of second ondemand PRS in a third band; measuring the second on demand PRS in thethird band; and sending, to the positioning entity, positioningmeasurements of the second on demand PRS.
 16. The method of claim 1,wherein: the UE transmits the first request to each of a first set ofbase stations, and the first on demand PRS are transmitted by the firstset of base stations.
 17. The method of claim 1, wherein: the UEtransmits the first request to a location server or a serving basestation, the first request is sent by the location server or the servingbase station to each of a first set of base stations, and the first ondemand PRS are transmitted by the first set of base stations.
 18. Themethod of claim 1, wherein: the first band comprises a first frequencyrange, a first frequency band, a first component carrier, or a firstpositioning frequency layer, and the second band comprises a secondfrequency range, a second frequency band, a second component carrier, ora second positioning frequency layer.
 19. The method of claim 1,wherein: the positioning entity comprises a positioning engine at theUE, and the method further comprises calculating a location of the UEbased on the positioning measurements of at least the first on demandPRS and the periodic PRS.
 20. The method of claim 1, wherein thepositioning entity comprises a location server or a serving basestation.
 21. A user equipment (UE), comprising: a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: cause the at least one transceiver to transmit, during apositioning session, a first request for transmission of first on demandpositioning reference signals (PRS) in a first band; measure, during thepositioning session, the first on demand PRS in the first band; measure,during the positioning session, periodic PRS transmitted in a secondband different from the first band, wherein the at least one processoris configured to transmit the first request for the transmission of thefirst on demand PRS in the first band and to measure the periodic PRStransmitted in the second band based on positioning requirements of thepositioning session; and send, to a positioning entity, positioningmeasurements of at least the first on demand PRS and the periodic PRS.22. The UE of claim 21, wherein the at least one processor is furtherconfigured to: cause the at least one transceiver to transmit, to alocation server, a capability message indicating that the UE can supportoperation on at least the first band and the second band.
 23. The UE ofclaim 20, wherein: the first on demand PRS are transmitted by a firstset of base stations, and the periodic PRS are transmitted by a secondset of base stations.
 24. The UE of claim 23, wherein: the first set ofbase stations is the same as the second set of base stations, or thefirst set of base stations is different from the second set of basestations.
 25. The UE of claim 23, wherein the at least one processor isfurther configured to: receive, from the location server via the atleast one transceiver, assistance information for at least the first setof base stations and the second set of base stations.
 26. The UE ofclaim 25, wherein the assistance information includes locations of atleast the first set of base stations and the second set of basestations.
 27. The UE of claim 25, wherein the assistance informationindicates at least a number of the first set of base stations operatingin the first band and a number of the second set of base stationsoperating in the second band.
 28. The UE of claim 23, wherein the atleast one processor is further configured to: determine at least anumber of the first set of base stations operating in the first band anda number of the second set of base stations operating in the second bandbased on detecting at least the first on demand PRS and the periodicPRS.
 29. A user equipment (UE), comprising: means for transmitting,during a positioning session, a first request for a first set of basestations to transmit first on demand positioning reference signals (PRS)in a first band; means for measuring, during the positioning session,the first on demand PRS from the first set of base stations in the firstband; means for measuring, during the positioning session, periodic PRSfrom a second set of base stations operating in a second band differentfrom the first band, wherein transmission of the first request for thetransmission of the first on demand PRS in the first band andmeasurement of the periodic PRS transmitted in the second band are basedon positioning requirements of the positioning session; and means forsending, to a positioning entity, positioning measurements of at leastthe first on demand PRS and the periodic PRS.
 30. A non-transitorycomputer-readable medium storing computer-executable instructions that,when executed by a user equipment (UE), cause the UE to: transmit,during a positioning session, a first request for a first set of basestations to transmit first on demand positioning reference signals (PRS)in a first band; measure, during the positioning session, the first ondemand PRS from the first set of base stations in the first band;measure, during the positioning session, periodic PRS from a second setof base stations operating in a second band different from the firstband, wherein transmission of the first request for the transmission ofthe first on demand PRS in the first band and measurement of theperiodic PRS transmitted in the second band are based on positioningrequirements of the positioning session; and send, to a positioningentity, positioning measurements of at least the first on demand PRS andthe periodic PRS.